JP2005130531A - Transmission level controlling method in subscriber type radio access system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a transmission level controlling method to control the generation of a higher transmission level than it is needed in a subscriber type radio access system. <P>SOLUTION: The subscriber type radio access system is constituted of: a step to generate a prescribed receiving level corresponding to each kind of data; a step to detect the receiving level of a data in a sending and receiving apparatus at a receiving side; a step to calculate a level difference between the detected receiving level and the prescribed receiving level corresponding to the kind of the receiving data; and a step to control a rise and fall of the receiving level in the sending and receiving apparatus at a transmission side according to the level difference. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

The present invention relates to a transmission / reception apparatus in a subscriber radio access system, and more particularly to control of a transmission level in the transmission / reception apparatus.
In recent years, the use of multimedia applications through the Internet has been rapidly spreading due to the rapid development of information communication technology and the accompanying increase in performance and price of information communication devices such as personal computers. In the future, various applications such as distance learning, medical treatment, and electronic commerce using the Internet are expected. Under such circumstances, there is an urgent need for faster networks, larger capacities, and lower prices, and the government policy is to develop a nationwide optical fiber network (FTTH) targeting 2010. : Fiber To The Home). However, 2010 is still a long way off, but even in 2010, it is difficult to lay optical fiber in all households, and it is difficult to lay down in units of villages (FTTC: Fiber To The Curb). There is also a way of thinking.

  From the above viewpoints, expectations for subscriber wireless access systems that lay high-speed and large-capacity lines in homes via wireless lines are growing. Yes. The present invention relates to this subscriber radio access system, and is a method for controlling the transmission level in a digital radio transceiver apparatus in a subscriber radio access system for time-division multiplex transmission of various data. In particular, a transmission level control method on the same channel in consideration of the reception level on the opposite side and the required reception level that differs for each type of data to be transmitted will be described.

FIG. 14 is a diagram schematically illustrating the concept of the subscriber radio access system.
In this figure, reference numeral 10 is a subscriber radio access system, and information is transmitted / received between a first transmission / reception device 11 and a second transmission / reception device 12 via a wireless transmission path 15.

The first transmission / reception device 11 is provided in the base station 13, for example. Moreover, the 2nd transmission / reception apparatus 12 is provided in each subscriber house 14, for example. However, in the following description, it may be assumed that the first transmission / reception device 11 is provided in the subscriber house 14 and the second transmission / reception device 12 is provided in the base station 13.
The base station 13 is connected to the public switched network PSTN through the radio link RL or the optical fiber OF.

As subscriber wireless access systems become more widespread, avoiding interference with other channels becomes more important. In addition, for the purpose of reducing power consumption, transmission must be performed with the minimum necessary output that can ensure line quality. Becomes essential.
Also, since the reception level on the opposite side varies due to rain attenuation, multipath fading, etc., control of the transmission level is important, and various control methods have been proposed so far.

  However, in the conventional transmission level control system for the relay system / core system, it is possible to monitor the reception level on the opposite side, BER (Bit Error Rate), etc., and realize the control of the minimum necessary transmission level. Alternatively, in ATM communication, a plurality of transmission information having different required BERs, such as a cell header part and a data part, are transmitted through a plurality of channels, and individual power control is performed.

  When trying to transmit various data with different required C / N (Carrier / Noise) and BER for each subscriber, as in the subscriber radio access system, in the above-described backbone / relay multiple lines In ATM communication, line design is performed on the same channel in accordance with the strictest required C / N, and the transmission level of the channel is determined. Therefore, there is a problem that transmission is performed with an excessive output when transmitting data whose required C / N conditions are not strict.

  In view of the above problems, the present invention suppresses an excessive level of transmission output as described above, and thus reduces power consumption and reduces interference with other lines. To provide a transmission level control method and a transmission / reception apparatus that enable transmission level control on the same channel by referring to the reception level and BER without considering distinction between continuous and non-continuous, and further considering the type of transmission data It is intended.

  Since bit errors are unavoidable on the wireless transmission path, circuit design is performed according to a certain standard regarding bit errors. The greater the degree of information compression, the greater the effect of bit errors. As a rough reference, the generally-known BER values are shown in Table 1 below (BER values corresponding to data types).

ここで、いずれのデータ種別についても変調方式が同一ならば、上記表１のＢＥＲに対して所要Ｃ／Ｎは、１対１に対応する。これより、データ種別毎に要求されるＢＥＲを満足する所要Ｃ／Ｎをもって回線設計を行うことにより、各データ種別毎に充分な回線品質の確保が可能となる。つまり同一の変調方式ならば、データ種別毎に、所要Ｃ／Ｎおよび必要な受信レベルも１対１に確定する。

Here, if the modulation scheme is the same for any data type, the required C / N for the BER in Table 1 corresponds one-to-one. Thus, by designing the line with the required C / N that satisfies the BER required for each data type, it is possible to ensure sufficient line quality for each data type. In other words, for the same modulation scheme, the required C / N and the required reception level are determined on a one-to-one basis for each data type.

  Therefore, in the present invention, the reception level on the opposite side is detected, the value of the reception level is compared with the required reception level corresponding to the type of data to be transmitted, and according to the level difference between the two levels. Control the increase or decrease of the transmission level. Generally speaking, the transmission level is increased for those with a low request BER (video and other errors are not allowed), and the transmission level is low for those with a high request BER (fax and other errors are allowed). .

  Most conventional transmission level control methods monitor the reception level, BER, etc. on the opposite side and realize control of the minimum necessary transmission level. In this case, since the required C / N is also fixed when the type of transmission data is fixed, this is not a problem. However, when various data having different required C / N and BER are to be transmitted, Since the line design is performed in accordance with the strictest required C / N and the transmission level is determined, when transmitting data with less strict C / N conditions, transmission is performed with an excessive output.

  In order to solve this problem, the present invention refers to the reception level on the opposite side without distinguishing between data continuity and discontinuity (packets, cells, etc.), and further, the required C / N according to the type of transmission data By referring to the reception level, it is possible to flexibly control the transmission level on the same channel. This makes it possible to secure sufficient line quality and reduce power consumption and interference with other lines.

FIG. 1 is a diagram showing basic steps of a transmission level control method according to the present invention.
The method according to the present invention comprises the illustrated steps in a subscriber radio access system that transmits data between one transmitting / receiving device and the other transmitting / receiving device via a wireless transmission path.
Step S1: Generate a required reception level (see Table 1 above) corresponding to each data type.

Step S2: The reception level of data in the receiving side transmission / reception apparatus (11 or 12) is detected.
Step S3: The detected reception level is compared with a required reception level corresponding to the type of the received data to obtain a level difference between the two reception levels.
Step S4: Control increase / decrease of the transmission level in the transmission / reception apparatus (12 or 11) according to the level difference.

FIG. 2 is a flowchart more specifically showing the steps shown in FIG.
Referring to this figure, first, when data is received, the type of data to be transmitted is identified (<1> identification of data type in FIG. 2).
Based on the required BER (Table 1) corresponding to the identified type of data, a reception level sufficient to ensure the line quality is generated (<2> generation of required reception level in FIG. 2).

  The reception level of the data at the receiving side transmission / reception device is measured and detected, and the detected reception level is compared with the required reception level. If the reception level is lower than the required reception level, increase the shortage of the transmission level, and conversely if the transmission level exceeds, keep the transmission level as it is, or exceed it. Is controlled (<3> transmission level control in FIG. 2).

  FIG. 3 is a block diagram showing a first embodiment of the first and second transmitting / receiving apparatuses according to the present invention. First, looking at the transmission / reception device 11 on the left side of the figure, this is the transmission / reception device 11 of the subscriber radio access system 10 that exchanges data via the wireless transmission path 15, and includes the required reception level generation means 21. The reception level acquisition unit 22, the comparison unit 23, and the transmission level control unit 24.

The required reception level generation means 21 identifies the type of data and generates a corresponding required reception level.
The reception level acquisition unit 22 acquires the reception level of the data in the opposite transmission / reception device 12 via the wireless transmission path 15.
The comparison means 23 compares the required reception level with the acquired reception level and outputs the level difference between the two.

The transmission level control means 24 controls the increase / decrease of the transmission level of the data to the opposite transmission / reception apparatus 12 according to the level difference.
On the other hand, the transmission / reception device 12 on the right side of FIG. 3 is also the transmission / reception device 12 of the subscriber wireless access system 10 that transmits and receives data via the wireless transmission path 15. 27 and reception level detection means 28.

The receiving means 26 receives the above data transmitted from the opposite transmission / reception device 11.
The transmission unit 27 transmits the data to the transmitting / receiving device 11 on the opposite side.
The reception level detection unit 28 detects the reception level of the data received by the reception unit 26.

Here, the transmission unit 27 transmits reception level information indicating the detected reception level to the transmitting / receiving device 11 on the opposite side via the wireless transmission path 15.
Explaining in more detail with reference to FIG. 3, in the transmission / reception apparatus 12 on the opposite side of the transmission / reception apparatus 11 in FIG. The level information is added to the data B to be transmitted to the transmission / reception device 11 and then transmitted through the duplexer 42. In the transmission / reception device 11, the required reception level that serves as a reference capable of securing the required BER is generated by the required reception level generation unit 34 based on the data type of the data A to be transmitted. Then, the comparison unit 35 compares the reception level information from the transmitter / receiver 12 obtained by the opposite side reception level extraction unit 36 from the receiver 37. When the reception level is lower than the reference value, the transmission level is increased by a shortage. When the reception level is exceeded, the transmission level is maintained, or the control is performed such that the transmission level is decreased. This is performed by the level increase / decrease unit 33.

Thus, in the first embodiment according to the present invention, the transmission level is controlled by the following steps.
First step: Receive level information indicating the receive level of data (data A) received by the transmitting / receiving device 12 on the opposite side is received.
Second step: Compare the reception level indicated in the received reception level information with the required reception level corresponding to the type of data (data A) to be transmitted to the transmitting / receiving device 12 on the opposite side.

Third step: Control the increase / decrease of the transmission level of data (data A) to be transmitted from the transmission / reception apparatus 11 according to the comparison result.
FIG. 4 is a block diagram showing a second embodiment of the first and second transmitting / receiving apparatuses according to the present invention. First, looking at the transmission / reception device 12 on the right side of the figure, this is the transmission / reception device 12 of the subscriber wireless access system 10 that exchanges data via the wireless transmission path 15, and includes the required reception level generation means 51 and the transmission / reception device 12. , Reception level detection means 52, comparison means 53, and transmission level increase / decrease information addition means 54.

The required reception level generating means 51 identifies the type of the data received from the opposite transmission / reception device 11 and generates a corresponding required reception level.
The reception level detection means 52 detects the reception level of the received data.
The comparison unit 53 compares the required reception level with the detected reception level and outputs a level difference between the two.

The transmission level increase / decrease information adding means 54 adds the transmission level increase / decrease information corresponding to the level difference to the data to be transmitted to the transmitting / receiving apparatus 11 on the opposite side.
On the other hand, the transmission / reception device 11 on the left side of FIG. 4 is also the transmission / reception device 11 of the subscriber wireless access system 10 that exchanges data via the wireless transmission path 15. And transmission level control means 58.

The receiving means 56 receives the above-mentioned data transmitted from the opposite transmission / reception device 12 together with transmission level increase / decrease information added to this data.
The transmission unit 57 transmits the data to the transmitting / receiving device 12 on the opposite side.
The transmission level control means 58 controls the increase / decrease of the transmission level of the data to the opposite transmission / reception apparatus 12 according to the transmission level increase / decrease information extracted from the reception means 56.

  In FIG. 4, the same reference numerals are assigned to the same functions as those shown in FIG. 3. Explaining in more detail along FIG. 4, the transmission / reception device 12 on the opposite side of the transmission / reception device 11 of FIG. 4 receives the required reception level generated based on the data type of the received data A and the receiver 41. The comparison unit 35 compares the reception level measured via the level measurement unit 43, and creates transmission level increase / decrease information based on the comparison result. For example, if the reception level is lower than the reference reception level, information indicating the amount of increase in transmission level according to the level difference is conversely exceeded. Alternatively, information indicating a transmission level reduction amount that should reduce the excess is added to the data B to be transmitted to the transmission / reception device 11 and transmitted. In the transmission / reception device 11, the transmission level is controlled by the transmitter 31 based on the transmission level increase / decrease information. The transmission level increase / decrease unit 33 performs this control.

Thus, in the second embodiment according to the present invention, the transmission level is controlled by the following steps.
First step: The type of data (data A) received by the transmission / reception device 12 is identified and a corresponding reception level is generated.
Second step: The reception level of the data (data A) received by the transmission / reception device 12 is detected.

Third step: The required reception level is compared with the detected reception level, and a level difference between the two is output.
Fourth step: The transmission level increase / decrease information corresponding to the level difference is added to the data (data B) to be transmitted from the transmission / reception device 12.
Fifth step: Control the increase / decrease of the transmission level of the data (data A) in the opposite transmission / reception device 11 according to the transmission level increase / decrease information added to the data (data B) from the transmission / reception device 12 and transmitted. To do.

Next, some examples of realization of the required reception level generation means (21, 51) described above will be described.
FIG. 5 is a diagram showing a first example for generating a required reception level. Reference numeral 61 denotes a change-over switch attached to the transmission / reception apparatus (11 in FIG. 3 or 12 in FIG. 4). When data to be transmitted is known in advance, data (data A) is obtained by the change-over switch 61 in advance. Determine the type of.

As a result, the required BER for each data type and the reception level required for it are determined (34).
By comparing (35) the reception level measured by the transmitting / receiving device 12 (FIG. 3) on the opposite side, the increase / decrease of the transmission level can be controlled (33). Reference numerals with () represent corresponding circuit parts in FIG.

  FIG. 6 is a diagram showing a second example for generating a required reception level. As shown in FIG. 6, a change-over switch 62 is attached to a transmission / reception apparatus (11 in FIG. 3), and a required BER is freely set in advance with a switch or a volume. As a result, a required reception level sufficient to secure the required BER is generated (34), and the increase / decrease in the transmission level can be controlled by comparing with the reception level (36) measured on the opposite side (35). (33) The line quality can be arbitrarily changed.

FIG. 7 is a diagram showing a third example for generating a required reception level.
When a terminal such as a personal computer is connected to the transmission / reception apparatus 11 (FIG. 3) to perform communication, the data type is switched in advance at the terminal by a switch or volume 63 on the software. Then, an identification bit for identifying the data type is added to the frame of the transmission data and transmitted to the transmission / reception apparatus 12 (31).

In the transmission / reception device 12, the identification bit added to the frame of the received data is read to generate a required reception level sufficient to secure the required BER of the data A (34), and the measured reception level ( 43), the increase / decrease of the transmission level can be controlled (54).
Table 2 described above is as follows, and is a table for converting BER represented by a × 10 ^−b into 6-bit information ABCDEF.

FIG. 8 is a diagram showing a fourth example for generating the required reception level.
When a terminal such as a personal computer is connected to the transmission / reception device 11 (FIG. 4), when data is transmitted from the terminal, the required BER is switched by the changeover switch 64 in advance on the software such as the computer. The required BER is converted into 6-bit data (the first 3 bits represent the multiplier of BER and the last 3 bits represent the absolute value of the exponent) according to Table 2 below, and added to the beginning of the data frame to be transmitted Then, the data is transmitted to the transmitting / receiving device 12.

  In the transmission / reception apparatus 12, the information of the added required BER is read, and a required reception level capable of securing the BER is generated (34).

図９は所要受信レベルを生成するための第５例を示す図である。
本図の７１は、送受信装置１１（図３）に用意されたインタフェース部であり、送信すべきデータ（データＡ）のデータ種別毎に異なるインタフェースのいずれがアクティブ（使用中）であるかに応じて、データ種別の識別がデータ種別識別部７２にて自動的になされる。そしてそのデータ種別の所要ＢＥＲを確保するのに充分な所要受信レベルを生成し（３４）、対向側の受信機における受信レベル（３６）と比較し（３５）、送信制御を行う（３３）。

FIG. 9 is a diagram showing a fifth example for generating a required reception level.
Reference numeral 71 in this figure denotes an interface unit prepared in the transmission / reception apparatus 11 (FIG. 3), which depends on which of the different interfaces is active (in use) for each data type of data to be transmitted (data A). The data type identification unit 72 automatically identifies the data type. Then, a required reception level sufficient to secure the required BER of the data type is generated (34), compared with the reception level (36) in the opposite receiver (35), and transmission control is performed (33).

FIG. 10 is a diagram showing a sixth example for generating a required reception level.
71 in this figure is an interface unit prepared in the transmission / reception apparatus 11 (FIG. 3) as in FIG. 9, and the required BER corresponding to each of the different interfaces for each data type of data (data A) to be transmitted is A reception level is generated that realizes a required BER for each data type of the input data (data A) given by the BER setting unit 73 (34). This reception level is compared with the reception level (36) in the transmitting / receiving device 12 (FIG. 3) on the opposite side (35), and transmission control is performed (33).
FIG. 11 is a diagram illustrating a seventh example for generating a required reception level.

When connecting a terminal such as a personal computer to the transmission / reception device, by incorporating a driver (for example, an identification bit adding unit 76 described later) into the computer and monitoring the extension of the transmission file by software in the terminal at the time of file transfer, For example, if the extension is . If wav, voice, . If it is mpg, the content of the transmission data is identified by the extension, such as a moving image. This is performed by the extension identifying unit 75. The identification result is added as an identification bit to the head of the frame of transmission data (data A). The identification bit adding unit 76 performs this. This is further transmitted to the transmitting / receiving device.

In the transmission / reception apparatus, the above-mentioned identification bit added is read to generate a required reception level sufficient to secure the required BER of the data (34). This required reception level and the reception level in the opposite transmission / reception apparatus (36) is compared (35), and transmission control is performed (33).
FIG. 12 is a diagram illustrating an eighth example of generating a required reception level.

When a terminal such as a personal computer is connected to the transmission / reception device, a driver (for example, an identification bit adding unit 77 described later) is incorporated in the computer, and the extension of the transmission file is monitored by software in the terminal during file transfer. For example, the extension is . If wav, voice, . If it is mpg, the content of the transmission data is identified by the extension, such as a moving image. This is performed by the extension identifying unit 75. Then, the required BER corresponding to the data belonging to the extension is converted into 6-bit data according to Table 2 described above, added as BER information to the head of the transmission data frame, and transmitted to the opposite transmission / reception device. . This is performed by the identification bit adding unit 77.

In the transmission / reception apparatus, a required reception level capable of securing the required BER indicated by the added BER information is generated (34), and the required reception level and the reception level (36) in the opposite transmission / reception apparatus are obtained. Compare (35) and perform transmission control (33).
FIG. 13 is a diagram for explaining adjustment when a required reception level is generated. This is a technique of individually adjusting the required BER according to the status of the subscriber radio access system.

In FIG. 13, when the type of data is identified, a predetermined BER (required BER) is assigned corresponding to each of various types such as video, text broadcasting, etc., and the required BER can be individually adjusted here. In the figure, an up / down switch 79 is shown as an example of the means for adjustment. For example, when viewing an image, 3.0 × 10 ⁻⁹ is displayed, for example 4.0 × 10 ⁻⁹ (up). Or it can be adjusted as 2.0 × 10 ⁻⁹ (down). This may be performed simultaneously for all the required BERs, or may be performed individually only for voice. How to adjust may be determined by the user adaptively according to the system status.

It is a figure showing the basic step of the transmission level control method based on this invention. It is a flowchart showing the step shown in FIG. 1 more concretely. It is a block diagram which shows 1st Example of the 1st and 2nd transmission / reception apparatus based on this invention. It is a block diagram which shows 2nd Example of the 1st and 2nd transmitter / receiver based on this invention. It is a figure which shows the 1st example for producing | generating a required reception level. It is a figure which shows the 2nd example for producing | generating a required reception level. It is a figure which shows the 3rd example for producing | generating a required reception level. It is a figure which shows the 4th example for producing | generating a required reception level. It is a figure which shows the 5th example for producing | generating a required reception level. It is a figure which shows the 6th example for producing | generating a required reception level. It is a figure which shows the 7th example for producing | generating a required reception level. It is a figure which shows the 8th example for producing | generating a required reception level. It is a figure for demonstrating the adjustment in the case of producing | generating a required reception level. It is a figure which illustrates the concept of a subscriber system wireless access system illustratively.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Subscriber system radio | wireless access system 11 1st transmission / reception apparatus 12 2nd transmission / reception apparatus 13 Base station 14 Subscriber house 15 Wireless transmission path 21 Required reception level production | generation means 22 Reception level acquisition means 23 Comparison means 24 Transmission level control means 26 Reception means 27 Transmission means 28 Reception level detection means 51 Required reception level generation means 52 Reception level detection means 53 Comparison means 54 Transmission level increase / decrease information addition means 56 Reception means 57 Transmission means 58 Transmission level control means 61, 62, 63, 64 switching Switch 71 Interface unit 72 Data type identification unit 73 BER setting unit 75 Extension identification unit 76, 77 Identification bit addition unit

Claims (5)

When the radio signal to be received relates to the first data, the first reference quality determined to satisfy the first data error quality required for the first data is set as the reference radio quality;
When the radio signal to be received is related to the second data, the second reference quality determined to satisfy the second data error quality required for the second data is set as the reference radio quality,
Comparing the set reference radio quality with the radio quality of the reception signal to be received;
A signal for transmission power control in the counterpart device is transmitted according to the comparison result.
A wireless transmission / reception method.   The wireless transmission / reception method according to claim 1, wherein the reference wireless quality is a reception level.   The wireless transmission / reception method according to claim 1, wherein the data error quality is a bit error rate of data. The first data is audio data, the second data is video data, the second data error quality is higher than the first data error quality, and the reference radio quality is also The second data is higher than the first data,
The wireless transmission / reception method according to claim 1. The first data is voice data, the second data is FAX data, the first data error quality is higher than the second data error quality, and the reference radio quality is also The first data is higher than the second data,
The wireless transmission / reception method according to claim 1.

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